Digital video and multimedia applications are becoming common place in the everyday life. Digital still cameras, DVD players and recorders, digital satellite broadcast and High-Definition televisions all implement digital audio and video compression technology. The digital media revolution has been the product of years of research by the private sector, and a great deal of investment from public entities and organizations. A multitude of formats describing the compressed audio, video and the encapsulating multiplex have been developed.
Typically, the multiplex format is simply a specification of how the audio and video data have been interleaved, and how audio and video can be separated from each other for the purpose of decoding individual streams. A multiplex may be made of a header portion, as well as a payload section, and information for performing trick-play and indexing operations. More importantly, the multiplex may convey information related to the framework of each stream, the method for performing audio/video synchronization, the overall stream sizes and individual sample-rates, and additional information pertinent to an individual encapsulated stream. Some multiplex formats allow updates to parts or all of descriptors, while other formats need the overall stream descriptions to remain consistent for part or all of the duration of the stream multiplex.
It would be desirable to provide a method and/or apparatus for altering the video frame-rate within the confines of a fixed-frame rate multiplex, to allow for the frame-rate conversion to take place through methods that are more widely employed and accepted, such as the repeating of interspersed fields rather than the repeating of two or more consecutive fields.